Support is requested for a Keystone Symposia meeting entitled Growing to Extremes: Cell Biology and Pathology of Axons, organized by Valeria Cavalli, Michael Fainzilber and Jeffery L. Twiss. The meeting will be held in Tahoe City, California from March 10 - 15, 2013. Neuronal communication is essential for every movement, sensation and thought in motile animals, and the axonal extensions of neurons provide all long- range communication to, from, and within the brain and spinal cord. Axons extend distances ranging from hundreds of microns to more than a meter in humans, lengths that both require specialized mechanisms for formation and maintenance, and increase the risk of degeneration and dysfunction upon injury or disease. Thus, diverse communities of basic researchers and clinicians must address problems rooted in axonal cell biology, but to date there is no meeting that serves as a central venue for this field. Axon biology meetings in the past have focused on specific sub-topics such as axon guidance, trophic factors, or neurodegeneration. This meeting will bring together the multiple disciplines required for accelerating progress in the field of axoal biology and pathology, providing a unique venue to bring together basic research on molecular and cellular biology of axons with clinical needs and industry interest. The conference will cover a broad spectrum of the latest developments in molecular and cellular axonal research, from development and maintenance, through to survival and repair, in both the central and peripheral nervous systems. Additional topics and late-breaking developments will be incorporated via talks selected from abstracts, specifically encouraging participation of junior researchers and those new to the field. The multidisciplinary theme and shared focus will facilitate communication across the entire continuum from basic to clinical neuroscience. PUBLIC HEALTH RELEVANCE: Neuronal communication is essential for every movement, sensation and thought in motile animals, and the axonal extensions of neurons provide all long-range communication to, from, and within the brain and spinal cord. The 2013 Keystone Symposia meeting on Growing to Extremes: Cell Biology and Pathology of Axons will provide a unique venue to bring together scientists working at the cutting edge of molecular and cellular biology of axons, axonal maintenance, and axonal transport. The purpose of this unique meeting is to bring together the multiple disciplines required for accelerating the progress in the field of axonal biology and pathology and to apply this understanding to the development of treatments for diseases and conditions rooted in axon biology.